Bipolar transistors with resistors

A method of forming an integrated circuit comprising:

• forming a MOS transistor on a substrate, comprising forming source and drain regions by implanting with a first dose of a dopant of a given polarity;
• forming a resistor on the substrate, comprising forming a body region by implanting with a second dose of the dopant, wherein the second dose implant occurs separately from the first dose implant;
• and
• forming a bipolar transistor on the substrate, comprising forming an emitter region by implanting with a third dose of the dopant;
• the third dose comprising the first dose of the dopant implanted simultaneously with the implant of the source and drain regions, and the second dose of the given type dopant implanted simultaneously with the implant of the body region.

A method of forming an integrated circuit on a semiconductor substrate including a MOS transistor with source/drain regions, a resistor with a body region, and a bipolar transistor with an emitter region, the method comprising:

• forming a first patterned mask over the substrate;
• in a first implant, implanting a first dopant into the emitter region and into one of the source/drain regions or the body region, with the other of the source/drain regions or the polysilicon body region covered against the first implant by the first patterned mask;
• forming a second patterned mask over the substrate;
• and
• in a second implant, implanting a second dopant of the same type polarity as the first dopant into the emitter region and into the other of the source/drain regions or the body region, with the one of the source/drain regions or the polysilicon body region covered against the second implant by the second patterned mask.